Preparation method of oxidized cellulose nano-fibril based on phosphoric acid and hydrogen peroxide

The invention discloses a preparation method of oxidized cellulose nano-fibril based on phosphoric acid and hydrogen peroxide. The preparation method comprises the following steps: mixing a biomass raw material, concentrated phosphoric acid with the mass concentration of 85 percent and hydrogen peroxide with the mass concentration of 50 percent; stirring and reacting for 96h under the condition that the temperature is 5 to 35 DEG C; then adding absolute ethyl alcohol for stopping reaction; standing the solution and layering; pouring out upper-layer supernatant and remaining lower-layer sediment; washing the lower-layer sediment by utilizing absolute ethyl alcohol, ethanol with the volume concentration of 50 percent and water in sequence; then treating by a high-pressure homogenizing machine to obtain the oxidized cellulose nano-fibril. The method disclosed by the invention has a simple and convenient technology; the variety of adopted chemical drugs is few and the chemical drugs are easy to obtain and low in